/Engine/Source/Editor/MainFrame/Public/Interfaces/IMainFrameModule.h
Generates a menu that includes application global commands, such as "Save All", "Exit", etc. If you're building a menu for your tab, you should call this function to create your menu, passing in an extender object to add your tab-specific menu items!
The newly-created menu widget
[TSharedRef](API\Runtime\Core\Templates\TSharedRef)< [SWidget](API\Runtime\SlateCore\Widgets\SWidget) > MakeMainMenu ( const [TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FTabManager](API\Runtime\Slate\Framework\Docking\FTabManager) > & TabManager, const [FName](API\Runtime\Core\UObject\FName) MenuName, [FToolMenuContext](API\Developer\ToolMenus\FToolMenuContext) & ToolMenuContext ) const